WASHINGTON (AP) — Fourteen men were charged with operating an online child exploitation network that investigators said preyed upon hundreds of boys across the United States and overseas, authorities announced Tuesday.

Law enforcement officials said the arrests were part of a worrisome trend in which children are being enticed into posting sexually explicit images of themselves. Those images are then broadly shared online. In this case, authorities said users of an underground network posed online as girls to coerce boys into sharing with them child pornography images.

"These alleged perpetrators preyed upon the most innocent, most vulnerable members of our society with no regard to the immediate or lasting harm they caused to their victims and their families," Homeland Security Secretary Jeh Johnson said.

The investigation was led by the U.S. Immigration and Customs Enforcement and U.S. Postal Inspection Service. The 250 victims were spread across 39 states and five other countries — Australia, Belgium, Britain, Canada and New Zealand. Most were boys between 13 and 15. Two victims were 3 or younger, authorities said.

The images and videos were shared on an underground website on the Tor network, an online anonymity network that masks the location of servers and conceals an Internet user's location. The subscription-based website operated from about June 2012 until June 2013 and had more than 27,000 members, authorities said.

Eleven of the 14 men, including the man authorities say was the administrator of the network, are being prosecuted in Louisiana. The other three are being charged in New York, Colorado and Wisconsin.

Authorities accuse Jonathan Johnson of of Abita Springs, La., of being the leader of the operation. They said he admitted creating multiple fake female personas from his home and encouraged others to do the same in an effort to entice boys to produce sexually explicit images of themselves.

Court papers show Johnson was charged last month through a criminal information, a document that can only be filed with a defendant's consent. It signals a guilty plea.

A lawyer for Johnson did not immediately return a call seeking comment on Tuesday.